Gage unit



E. D. REED GAGE UNIT April 17, 1956 Filed Dec. 19, 1952 ATTO/PA/f/J 020? ZJ P L Z United States Patent GAGE UNIT Edwin D. Reed, Detroit, Mich.

Application December 19, 1952, Serial No. 326,928

3 Claims. (Cl. 33-178) This invention relates to a gage unit and more particularly to a gage especially adapted for gaging the diameter of blind holes or counterbores.

It is an object of this invention to provide a gage unit of the above type which is adaptable for gaging holes or ccunterbores throughout a wide range of diameters.

A further object of the invention is to provide a gage unit which includes a handle and a plurality of gage members each of which may be selectively inserted or removed from the handle so as to adapt the unit for gaging holes of widely diiferent sizes.

A further object of the invention resides in the provision of a gage unit which is especially adapted for gaging the diameter of a blind hole or a counterbore in a plane closely adjacent the base of the hole or counterbore.

In the drawings:

Fig. l is a side elevation of a gage unit of this invention.

Fig. 2 is a sectional view taken along the line 22 in Fig. 1.

Fig. 3 is a fragmentary sectional view taken along the line 33 in Fig. 1.

Fig. 4 is a bottom view of a gage unit with the gage head in an expanded position.

Fig. 5 is a sectional view taken along the line 5-5 in Fig. 4.

Fig. 6 is a bottom view of a gage member of modified construction.

Fig. 7 is a fragmentary side elevation of the gage member shown in Fig. 6.

Fig. 8 is a bottom view of a further modified member.

Fig. 9 is a fragmentary side elevation of the member shown in Fig. 8.

The gage unit of this invention generally includes a handle member 10 and a removable gage member 12. Handle 10 comprises a sleeve 14 at the upper end of which is rotatably supported as by the spring clip 16 a knob 18 having a tubular extension 20 received within sleeve 14. Extension 26 is internally threaded as at 22. Gage member 12 includes a stem portion 24 which is dimensioned to have a slip fit in bore 25 at the lower end of sleeve 14.

At its lower end stem 24 is provided with an enlarged generaHy circular head 26. Stem 24 and head 26 are axially slotted as at 28 so as to divide head 26 into two half portions 26:: and 26b. Slot 28 extends diametrically through stem 24 and head 26 and extends upwardly from head 26 and terminates as at 36 at a point spaced downwardly from the upper end of stem 24. Stem 24 is provided with a central bore 32 which is shaped as a conical socket 34 at the lower face of head 26. Within bore 32 there is arranged an operating rod 36 which is threaded at its upper end as at 38 for threaded engagement with the threaded bore 22 of knob 13.

At its lower end rod 36 is provided with a conicallyshaped head which, when the rod 36 is moved axially age gage

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inwardly of handle 10, engages the comically-shaped socket 34 to cause the head members 26a and 26b to expand or separate in a direction perpendicular to slot 28. Axial movement of rod 36 is produced by turning knob 18 in either one direction or the other to thereby thread the upper end 38 of rod 36 into or out of the threaded bore 22 of knob 18. In order to prevent rod 36 from turning with knob 18 the head 40 of the operating rod is provided with a projecting detent 42 which engages in slot 28 and slides axially therein as the rod 36 moves axially within stem 24.

In order to permit accurate gaging of the diameter of a blind hole such as shown at 44 in a plane closely.

adjacent the bottom 46 of the hole, the lower face of head 26 is slotted or recessed as at 48. Recess 48 extends across head 26 in the same direction as slot 28, thus providing on the lower face of head 26 two diametrically opposite pads 58a and 5%. It will be observed that the pads 50a and 56b are located along the diameter of greatest dimension when the head 26 is expanded.

One of the features of the present invention resides in the provision of several gage members 12 for insertion into the lower end of sleeve 14. In order to provide for an effective means for locking a gage member such as shown at 12 in the lower end of sleeve 14 there is pro vided some sort of locking means preferably in the form of a pin 52 at the upper end of stem 24 which projects through a slot 54 in the side wall of sleeve 14. Slot 54 has a portion 56 extending axially of sleeve 14 and another portion 58 which extends perpendicular to the.

axially extending portion 56. The portion 58 of slot 54 is dimensioned in width to have a nice fit with pin 52. Thus, when stem 24 is inserted into the lower end of sleeve 14 and thereafter turned slightly to engage pin 52 in the slot portion 58 the gage member 12 is effectively locked against axial movement on handle 10.

The gage members 12 are preferably provided as a series of progressively increasing diameters so that the gage unit of this invention may be employed for gaging holes within a wide range of diameters. Thus, there is provided, for example, a gage member 12 with a head 66 having a diameter greater than the head 26; and there may also be provided another gagernember 12 having a head 62 which has a diameter greater than the diameter of head 60. The arrangement is such that the diameter of head 60 is slightly less than the maximum diameter of the head 26 when expanded, and the head 62 is slightly less in diameter than the maximum diameter of the head 69 when expanded.

The purpose in forming the slot 48 is to remove the center bottom portion of the metal in the head of the gage member so that, when the head is expanded, the pads Sila and 591) will contact in the bottom 46 of the hole or counterbore being gaged. The clearance provided by slot 43 may be produced by any suitable machining operation, and the configuration of the slot 48 may vary, it being realized that the purpose of such slot is simply to provide small pads such as shown at 5th: and 50b which, when the head is expanded, will contact the bottom of the hole or counterbore being gaged so that the circumferential edges of the head adjacent the pads 50a and Sill) will contact the side walls of the hole closely adjacent the bottom 46 of the hole. Thus, for example, instead of forming the slot 48 by simply a straight milling operation across the lower face of the head such as shown in Figs. 4 and 6, the recess in the lower face of the head may be provided by slotting the lower face of the head as at 64 and thereafter providing a circular groove 66 which enlarges the recess provided by the slot 64 and provides the necessary clearance along the line of maximum diameter when the head is expanded.

Thus, it will be seen that I have provided a gage unit member 12 and the sleeve 14. Relative adapted to be readily connected with a handle member enables the gage to be used with different holes which vary widelyin size. It will furthermore be appreciated that the provision of the pin-slot connection such asshown at 54, 58 insures accurate gaging, since this construction prevents relative axial movement of the age lilOf'Jl'ii 1; of these members must be prevented to produce accurate results, since the sonically-shaped head 40 engages the edges of the conically-shaped opening 34 in the lower face of the head of the gage member 12 and therefore would tend to expand or contract the head it moved relative to the head in an axial direction.

I claim:

l. A gage comprising a handle provided with a turning member mounted at one end thereof in an axially fixed position, a gage member projecting from the opposite end of said handle, said gage member having a generally circular head at the free end thereof, said head being diametrically divided by a relatively narrow slot into two half sections, means engageable with said turning member for causing said half sections to separate and thereby increase the etiective diameter of said head in a direction perpendicular to the slot between said half sections, and a pair of fiat pads at the axial extremity of said head, said pads being positioned diametricall opposite along the line of maximum diameter when the head of the gage member is expanded, said pads being substantially smaller than said head in axial projection and each extending around only a portion of the circumferential edge of said half sections which is radially outermost from said slot.

2. A gage comprising a handle provided with a turning member mounted at one end thereof in an axially fixed position, a gage member projecting from the opposite end of said handle, said gage member having a generally circular head at the free end thereof, said head being diametrically divided by a central slot into two separable half sections, means engageable with said turning member for causing said half sections to separate and thereby increase the efiective diameter of said head in a direction perpendicular to the line of division between said half sections, the axialend face of said head lying in a plane generally perpendicular to said handle, said head being of greatest diameter at said axial end face, the axial end face of said head being recessed on opposite sides of said central slot throughout a major portion thereof to provide a pair of relatively small pads which are positioned diametrically opposite along the line of maximum diameter when the head of the gage member is expanded,

said pads being substantially smaller than said head in axial projection and the radially innermost edges of said pads being spaced radially outwardly from said slot a distance equal to at least half the radius of said axial end face. i

3. A gage comprising a handle provided with a turning member mounted at one end thereof in an axially fixed position, a gage member projecting from the opposite end of said handle, said gage member having a generally circular head at the free end thereof, said head being diametrically divided by a central slot into two separable half sections, means engageable with said turning member for causing said half sections to separate and thereby increase the effective diameter of said head in a direction perpendicular to the line of division between said halt sections, the axial end face of said half sections each raving an axially projecting portion spaced radially from said central slot and extending around only a portion of the circumferential edge of said half sections, said projecting portions being positioned diametrically opposite along a line perpendicular to the line of division between said half sections, each of said axially projecting portions having its radially inner edge terminating on said end face along a line spaced substantially radially outwardly from said central slot, said axial projections being relatively small in size as compared with the size of said half sections in axial projection.

References Cited in the file of this patent UNITED STATES PATENTS Great Britain Dec. 5, 

